[prometheus-node-exporter] support digest and full image refs in image.tag

charts/prometheus-node-exporter/Chart.yaml

@@ -6,7 +6,7 @@ keywords:
   - prometheus
   - exporter
 type: application
-version: 4.56.1
+version: 4.56.2
 # renovate: github=prometheus/node_exporter
 appVersion: 1.12.1
 home: https://github.com/prometheus/node_exporter/

charts/prometheus-node-exporter/templates/_helpers.tpl

@@ -72,11 +72,17 @@ Create the name of the service account to use
 {{- end }}
 
 {{/*
-The image to use
+The image to use.
+
+If image.tag contains "/", treat it as a full image reference (optionally with
+@digest) and use it as-is. Prefer image.registry/repository/tag (+ image.digest)
+for the normal case.
 */}}
 {{- define "prometheus-node-exporter.image" -}}
 {{- if .Values.image.sha }}
 {{- fail "image.sha forbidden. Use image.digest instead" }}
+{{- else if and .Values.image.tag (contains "/" (.Values.image.tag | toString)) }}
+{{- .Values.image.tag }}
 {{- else if .Values.image.digest }}
 {{- if .Values.global.imageRegistry }}
 {{- printf "%s/%s:%s%s@%s" .Values.global.imageRegistry .Values.image.repository (default (printf "v%s" .Chart.AppVersion) .Values.image.tag) (ternary "-distroless" "" .Values.image.distroless) .Values.image.digest }}
@@ -92,6 +98,23 @@ The image to use
 {{- end }}
 {{- end }}
 
+{{/*
+Semver used for feature gates (semverCompare). Prefers Values.version, then
+image.tag, then Chart.AppVersion. Normalizes common image-ref forms:
+- tag@sha256:...
+- registry/repository:tag[@digest]
+- registry:port/repository:tag[@digest]
+*/}}
+{{- define "prometheus-node-exporter.appSemver" -}}
+{{- $raw := coalesce .Values.version .Values.image.tag .Chart.AppVersion | toString -}}
+{{- $noDigest := ternary (index (splitList "@" $raw) 0) $raw (contains "@" $raw) -}}
+{{- if contains "/" $noDigest -}}
+{{- last (splitList ":" $noDigest) -}}
+{{- else -}}
+{{- $noDigest -}}
+{{- end -}}
+{{- end -}}
+
 {{/*
 Allow the release namespace to be overridden for multi-namespace deployments in combined charts
 */}}

charts/prometheus-node-exporter/templates/daemonset.yaml

@@ -104,7 +104,7 @@ spec:
             - --path.sysfs=/host/sys
             {{- if .Values.hostRootFsMount.enabled }}
             - --path.rootfs=/host/root
-            {{- if semverCompare ">=1.4.0-0" (coalesce .Values.version .Values.image.tag .Chart.AppVersion) }}
+            {{- if semverCompare ">=1.4.0-0" (include "prometheus-node-exporter.appSemver" .) }}
             - --path.udev.data=/host/root/run/udev/data
             {{- end }}
             {{- end }}

charts/prometheus-node-exporter/unittests/daemonset_image_semver_test.yaml

@@ -0,0 +1,55 @@
+# yaml-language-server: $schema=https://raw.githubusercontent.com/helm-unittest/helm-unittest/main/schema/helm-testsuite.json
+suite: daemonset image and semver feature gates
+templates:
+  - daemonset.yaml
+tests:
+  - it: includes udev path arg with default chart appVersion
+    asserts:
+      - contains:
+          path: spec.template.spec.containers[0].args
+          content: --path.udev.data=/host/root/run/udev/data
+      - equal:
+          path: spec.template.spec.containers[0].image
+          value: quay.io/prometheus/node-exporter:v1.12.1
+
+  - it: includes udev path arg when image.tag has digest pin
+    set:
+      image.tag: v1.12.1@sha256:aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+    asserts:
+      - contains:
+          path: spec.template.spec.containers[0].args
+          content: --path.udev.data=/host/root/run/udev/data
+      - equal:
+          path: spec.template.spec.containers[0].image
+          value: quay.io/prometheus/node-exporter:v1.12.1@sha256:aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+
+  - it: includes udev path arg and uses full image ref from image.tag
+    set:
+      image.tag: quay.io/prometheus/node-exporter:v1.6.0@sha256:d2e48098c364e61ee62d9016eed863b66331d87cf67146f2068b70ed9d9b4f98
+    asserts:
+      - contains:
+          path: spec.template.spec.containers[0].args
+          content: --path.udev.data=/host/root/run/udev/data
+      - equal:
+          path: spec.template.spec.containers[0].image
+          value: quay.io/prometheus/node-exporter:v1.6.0@sha256:d2e48098c364e61ee62d9016eed863b66331d87cf67146f2068b70ed9d9b4f98
+
+  - it: omits udev path arg when app semver is below 1.4.0
+    set:
+      image.tag: v1.3.1
+    asserts:
+      - notContains:
+          path: spec.template.spec.containers[0].args
+          content: --path.udev.data=/host/root/run/udev/data
+
+  - it: uses Values.version for feature gate when image.tag is not semver
+    set:
+      image.tag: latest
+      version: 1.12.1
+    asserts:
+      - contains:
+          path: spec.template.spec.containers[0].args
+          content: --path.udev.data=/host/root/run/udev/data
+      - equal:
+          path: spec.template.spec.containers[0].image
+          value: quay.io/prometheus/node-exporter:latest

charts/prometheus-node-exporter/values.yaml

@@ -646,5 +646,7 @@ extraVolumeMounts: []
   #   mountPath: /extra
   #   readOnly: true
 
-# Override version of app, required if image.tag is defined and does not follow semver
+# Override app version for feature gates when image.tag is not a plain semver
+# (for example "latest"). Digests and full image refs in image.tag are normalized
+# automatically for comparison; use image.digest when pinning with registry/repository.
 version: ""